AB1638 RISK FACTORS FOR DEVELOPING RHEUMATIC IMMUNE-RELATED ADVERSE EVENTS AFTER IMMUNOTHERAPY WITH IMMUNE CHECKPOINT INHIBITORS
Authors: M. Liapi, K. Chatzidionysiou
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Immunotherapy with monoclonal antibodies that block specific immunological check-points has revolutionized the treatment of some forms of cancer, such as melanoma. A new group of adverse events has emerged with these new agents, called the immune-related adverse events (irAEs). Among these irAEs, rheumatic complications are relatively common, although the true frequency is still unclear. <h3>Objectives</h3> We aimed to assess the frequency of ir-AEs and rheumatic ir-AEs in particular, as well as identifying potential risk factors for irAEs in a cohort of patients with malignant melanoma receiving immunotherapy with immune checkpoint inhibitors (ICI). <h3>Methods</h3> Retrospective analysis of a cohort of patients diagnosed with malignant melanoma and starting treatment with a first-ever ICI at Karolinska University Hospital between 2012 and 2020. The type of irAEs, glucocorticoid therapy at immunotherapy start, demographics and type of ICI were collected from patient's journals. <h3>Results</h3> A total of 118 patients were included in the cohort, 75 male (63,6%) and 43 females (36,4%). The type of ICI was nivolumab in 54.2% of patients, ipilimumab in 13.6%, pembrolizumab in 22.9% and combination therapy with ipilimumab and nivolumab in 7.6%, ipilimumab and pembrolizumab in 0.8% and nivolumab and pembrolizumab in 0.9%. Any irAE developed 72/118 patients (61%), while rheumatic irAEs were seen in 24 patients (20.3%) with the following clinical phenotypes; arthralgia/myalgia in 9 patients (37.5%), PMR like syndrome in 3 patients (12.5%), arthritis in 6 patients (25%), sicca syndrome in 4 patients (16%), sarcoidosis in 1 patient (4.2%) and myositis in 1 patient (4.1%). There was no significant association between the type of ICIs or combination therapy in total with the development av irAEs (OR = 1.79, 95% CI = 0.45 – 7.1, p=0.39). Neither the gender (OR 1.12, 95% CI = 0.52-2.40, p=0.76) nor the glucocorticoid use at the ICI start were associated with the development av irAEs [OR=2.0, 95% CI = 0.38 – 10.36, p=0.38]. No significant associations were observed between demographic factors (age, gender), type of ICI, glucocorticoid use at the start of ICI and rheumatic irAEs. <h3>Conclusion</h3> IrAEs are common and occur in more than half of patients treated with ICI. Rheumatic irAEs are also common and in this study were seen in one fifth of patients. Gender, age, type of ICI and treatment with glucocorticoids at baseline are not associated with increased (or decreased) risk for irAEs in general, or rheumatic irAEs in particular, in this cohort of patients with melanoma, with the risk of type II error due to limited power. <h3>Reference</h3> [1]Calabrese LH, Calabrese C, Cappelli LC. Rheumatic immune-related adverse events from cancer immunotherapy. Nat Rev Rheumatol. 2018 Oct;14(10):569-579. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> Matina Liapi: None declared, Katerina Chatzidionysiou Grant/research support from: Galapagos.